Women during gestation or lactation. Bypass vessel disease after coronary artery bypass grafting (CABG). Any other brand of coronary artery stent has been implanted. Patients with impaired fast glucose level (6.0mmol/L-7.0mmol/L) or impaired carbohydrate tolerance (OGTT 2h glucose level within 7.8mmol/L-11.1mmol/L).